Shain Gandee, Buckwild

Gandee was just 21 when he and two others were discovered dead in his truck on April 1, 2013. According to the West Virginia Sheriff's Department, the MTV star and his companions died of carbon monoxide poisoning when the vehicle -- and its muffler -- got stuck in the mud. "This is the emptiest I've ever felt," costar Cara Parrish tweeted after his passing. She and hundreds of camo-wearing friends and fans paid tribute to Gandee a week later at his funeral.